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An Educational Resource for Sufferers with Kidney Stones
by Roger Baxter
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Preventing Kidney Stone Formation

The easiest step to take is to increase hydration. This applies to sufferers of all types of kidney stones. Drinking very large amounts of water — two or more quarts per day — is probably the most important step in reducing stone formation. It is recommended that sufferers increase their urine output to at least 2 quarts per 24 hour period. Drinking 2 to 3 quarts per day may reduce recurrence of stones by up to 90 percent.

Initially many kidney stone sufferers may find it difficult to raise their fluid intake to this level. However, with a consistent conscious effort a person will develop a taste for water. After about a month their body will readjust its normal level of hydration. Once this new norm has become established a person will start to feel thirsty whenever their fluid intake falls below this level. Some tips on increasing fluid intake may prove helpful. One kidney stone sufferer says: I like water now. You acquire a taste for it.

High calcium in urine can be caused by too much salt in a person's diet. Salt causes excretion of larger amounts of calcium and thus increases calcium in the urine. Increasing a person's intake of water will reduce the relative concentration of calcium in the urine and thus reduce the risk of crystal formation and kidney stone formation.

Additionally, persons prone to the most common type of kidney stones (calcium oxalate) may find it advisable to cut back on foods with high oxalate levels such as those listed below to help prevent future stone formation:

  • apples
  • asparagus
  • beer
  • beets
  • berries, various
  • black pepper
  • broccoli
  • cheese
  • chocolate
  • cocoa
  • coffee
  • cola drinks
  • collards
  • figs
  • grapes
  • ice cream
  • milk
  • oranges
  • parsley
  • peanut butter
  • pineapples
  • spinach
  • Swiss chard
  • rhubarb
  • tea
  • turnips
  • vitamin C
  • yogurt

Stone suffers should consult with their doctor, of course, but in most cases, these foods can be eaten in limited amounts.

A diet with high levels of sodium, sucrose, or animal protein increase the likelihood of kidney stone formation. Conversely, high levels of potassium, magnesium, and fluids lower the likelihood of kidney stone formation. There are, also, medications available to reduce the tendency towards formation of certain types of stones.

One type of medication to reduce risk of formation of calcium oxalate stones introduces high levels of citrate into the kidneys. This citrate in the urine reduces the tendency for calcium oxalate stone formation. A similar increase in urinary citrate is generated by drinking lemonade (lemons are one of the good foods) containing at least 4 ounces of lemon juice per day.

It has been discovered that avoiding calcium may do more harm than good when it comes to kidney stone sufferers who have, in the past, been warned to avoid foods rich in calcium. According to a study of over 45,000 men conducted by the Harvard School of Public Health, men who get lots of calcium in their diets have a one-third lower risk of having kidney stones than do those who consume calcium sparingly. It seems that high dietary calcium actually blocks a chemical action which causes the formation of kidney stones by binding with oxalates (from foods) in the intestine which then prevents both from being absorbed into the blood stream and later transferred to the kidneys. Urinary oxalate may be more important to formation of calcium-oxalate kidney stone crystals than is the urinary calcium.

However it must be quickly noted here that calcium supplements increase kidney stone risks according to the Annuals of Internal Medicine, March 1997. High normal dietary calcium reduces kidney stones by 35 percent, but high calcium from non-foods — like calcium supplements — actually increase the risk of kidney stones by 20 percent.

That same Harvard study found that:

  • Those with the highest consumption of potassium, from eating fruits and vegetables, had only half the risk of stones;
  • A high fluid intake was associated with a 29 percent lower risk; and
  • Those who ate the most animal protein had a 33 percent higher risk of developing kidney stones.

Winning the battle with kidney stones is a two stage war. The first hurdle — which is sometimes elected to be skipped by doctors and patients — is to become stone free to reduce later stone formation due to the presence of those existing stone crystals. Then the second hurdle is to eliminate (or at least reduce) the risk factors that might lead to formation of new kidney stones.

A review of the information on kidney stones every 3 to 6 months may be necessary to keep the benefits and importance of constant and long term viligence at the stone prevention process in the sufferer's conscious mind.

©1997-2018 Roger Baxter

Latest update October 2, 2018